A QoS Internet protocol scheduler on the IXP1200 network platform

In this paper we describe the implementation of a scheduler capable of Quality of Service (QoS) management on the Intel IXP 1200 network processor. First, the scheduling algorithm PTTSD is introduced at the abstract level showing its characteristics and complexity. Then, the IXP architecture is briefly described with the purpose of refining the PTTSD algorithm in order to provide a more efficient implementation. The refined PTTSD scheduler has been implemented on top of the reference design provided by Intel. The dependency of the adopted software architecture on the IXP network processor is analyzed and, finally, the implementation is described. A set of characterization tests is reported to demonstrate the efficiency of the implementation and the effectiveness of the Intel architecture to implement flexible QoS routers.